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<FONT color="green">001</FONT>    <a name="line.1"></a>
<FONT color="green">002</FONT>    /*<a name="line.2"></a>
<FONT color="green">003</FONT>     * Copyright (C) 2011 Archie L. Cobbs. All rights reserved.<a name="line.3"></a>
<FONT color="green">004</FONT>     *<a name="line.4"></a>
<FONT color="green">005</FONT>     * $Id: AbstractUpdatingDataSource.html 9 2011-02-08 16:45:47Z archie.cobbs $<a name="line.5"></a>
<FONT color="green">006</FONT>     */<a name="line.6"></a>
<FONT color="green">007</FONT>    <a name="line.7"></a>
<FONT color="green">008</FONT>    package org.dellroad.stuff.schema;<a name="line.8"></a>
<FONT color="green">009</FONT>    <a name="line.9"></a>
<FONT color="green">010</FONT>    import java.io.PrintWriter;<a name="line.10"></a>
<FONT color="green">011</FONT>    import java.sql.Connection;<a name="line.11"></a>
<FONT color="green">012</FONT>    import java.sql.SQLException;<a name="line.12"></a>
<FONT color="green">013</FONT>    <a name="line.13"></a>
<FONT color="green">014</FONT>    import javax.sql.DataSource;<a name="line.14"></a>
<FONT color="green">015</FONT>    <a name="line.15"></a>
<FONT color="green">016</FONT>    /**<a name="line.16"></a>
<FONT color="green">017</FONT>     * A {@link DataSource} that wraps an inner {@link DataSource} and automatically performs some update<a name="line.17"></a>
<FONT color="green">018</FONT>     * operation on the inner {@link DataSource} on first access.<a name="line.18"></a>
<FONT color="green">019</FONT>     */<a name="line.19"></a>
<FONT color="green">020</FONT>    public abstract class AbstractUpdatingDataSource implements DataSource {<a name="line.20"></a>
<FONT color="green">021</FONT>    <a name="line.21"></a>
<FONT color="green">022</FONT>        private DataSource dataSource;<a name="line.22"></a>
<FONT color="green">023</FONT>        private boolean updated;<a name="line.23"></a>
<FONT color="green">024</FONT>    <a name="line.24"></a>
<FONT color="green">025</FONT>        /**<a name="line.25"></a>
<FONT color="green">026</FONT>         * Configure the underlying {@link DataSource}. Required property.<a name="line.26"></a>
<FONT color="green">027</FONT>         */<a name="line.27"></a>
<FONT color="green">028</FONT>        public void setDataSource(DataSource dataSource) {<a name="line.28"></a>
<FONT color="green">029</FONT>            this.dataSource = dataSource;<a name="line.29"></a>
<FONT color="green">030</FONT>        }<a name="line.30"></a>
<FONT color="green">031</FONT>    <a name="line.31"></a>
<FONT color="green">032</FONT>        /**<a name="line.32"></a>
<FONT color="green">033</FONT>         * Update the inner {@link DataSource}.<a name="line.33"></a>
<FONT color="green">034</FONT>         *<a name="line.34"></a>
<FONT color="green">035</FONT>         * &lt;p&gt;<a name="line.35"></a>
<FONT color="green">036</FONT>         * This method will be invoked at most once.<a name="line.36"></a>
<FONT color="green">037</FONT>         */<a name="line.37"></a>
<FONT color="green">038</FONT>        protected abstract void updateDataSource(DataSource dataSource) throws SQLException;<a name="line.38"></a>
<FONT color="green">039</FONT>    <a name="line.39"></a>
<FONT color="green">040</FONT>        /**<a name="line.40"></a>
<FONT color="green">041</FONT>         * Get the underlying {@link DataSource}.<a name="line.41"></a>
<FONT color="green">042</FONT>         */<a name="line.42"></a>
<FONT color="green">043</FONT>        protected DataSource getInnerDataSource() {<a name="line.43"></a>
<FONT color="green">044</FONT>            return this.dataSource;<a name="line.44"></a>
<FONT color="green">045</FONT>        }<a name="line.45"></a>
<FONT color="green">046</FONT>    <a name="line.46"></a>
<FONT color="green">047</FONT>        /**<a name="line.47"></a>
<FONT color="green">048</FONT>         * Determine if the underlying {@link DataSource} has been updated.<a name="line.48"></a>
<FONT color="green">049</FONT>         *<a name="line.49"></a>
<FONT color="green">050</FONT>         * &lt;p&gt;<a name="line.50"></a>
<FONT color="green">051</FONT>         * If the update is currently happening in another thread, the current thread will<a name="line.51"></a>
<FONT color="green">052</FONT>         * block until the update operation finishes.<a name="line.52"></a>
<FONT color="green">053</FONT>         */<a name="line.53"></a>
<FONT color="green">054</FONT>        protected synchronized boolean isUpdated() {<a name="line.54"></a>
<FONT color="green">055</FONT>            return this.updated;<a name="line.55"></a>
<FONT color="green">056</FONT>        }<a name="line.56"></a>
<FONT color="green">057</FONT>    <a name="line.57"></a>
<FONT color="green">058</FONT>        // DataSource methods<a name="line.58"></a>
<FONT color="green">059</FONT>    <a name="line.59"></a>
<FONT color="green">060</FONT>        @Override<a name="line.60"></a>
<FONT color="green">061</FONT>        public Connection getConnection() throws SQLException {<a name="line.61"></a>
<FONT color="green">062</FONT>            return getUpdatedDataSource().getConnection();<a name="line.62"></a>
<FONT color="green">063</FONT>        }<a name="line.63"></a>
<FONT color="green">064</FONT>    <a name="line.64"></a>
<FONT color="green">065</FONT>        @Override<a name="line.65"></a>
<FONT color="green">066</FONT>        public Connection getConnection(String username, String password) throws SQLException {<a name="line.66"></a>
<FONT color="green">067</FONT>            return getUpdatedDataSource().getConnection(username, password);<a name="line.67"></a>
<FONT color="green">068</FONT>        }<a name="line.68"></a>
<FONT color="green">069</FONT>    <a name="line.69"></a>
<FONT color="green">070</FONT>        @Override<a name="line.70"></a>
<FONT color="green">071</FONT>        public PrintWriter getLogWriter() throws SQLException {<a name="line.71"></a>
<FONT color="green">072</FONT>            return getUpdatedDataSource().getLogWriter();<a name="line.72"></a>
<FONT color="green">073</FONT>        }<a name="line.73"></a>
<FONT color="green">074</FONT>    <a name="line.74"></a>
<FONT color="green">075</FONT>        @Override<a name="line.75"></a>
<FONT color="green">076</FONT>        public void setLogWriter(PrintWriter pw) throws SQLException {<a name="line.76"></a>
<FONT color="green">077</FONT>            getUpdatedDataSource().setLogWriter(pw);<a name="line.77"></a>
<FONT color="green">078</FONT>        }<a name="line.78"></a>
<FONT color="green">079</FONT>    <a name="line.79"></a>
<FONT color="green">080</FONT>        @Override<a name="line.80"></a>
<FONT color="green">081</FONT>        public void setLoginTimeout(int timeout) throws SQLException {<a name="line.81"></a>
<FONT color="green">082</FONT>            getUpdatedDataSource().setLoginTimeout(timeout);<a name="line.82"></a>
<FONT color="green">083</FONT>        }<a name="line.83"></a>
<FONT color="green">084</FONT>    <a name="line.84"></a>
<FONT color="green">085</FONT>        @Override<a name="line.85"></a>
<FONT color="green">086</FONT>        public int getLoginTimeout() throws SQLException {<a name="line.86"></a>
<FONT color="green">087</FONT>            return getUpdatedDataSource().getLoginTimeout();<a name="line.87"></a>
<FONT color="green">088</FONT>        }<a name="line.88"></a>
<FONT color="green">089</FONT>    <a name="line.89"></a>
<FONT color="green">090</FONT>        @Override<a name="line.90"></a>
<FONT color="green">091</FONT>        public &lt;T&gt; T unwrap(Class&lt;T&gt; cl) throws SQLException {<a name="line.91"></a>
<FONT color="green">092</FONT>            return cl.cast(getUpdatedDataSource());<a name="line.92"></a>
<FONT color="green">093</FONT>        }<a name="line.93"></a>
<FONT color="green">094</FONT>    <a name="line.94"></a>
<FONT color="green">095</FONT>        @Override<a name="line.95"></a>
<FONT color="green">096</FONT>        public boolean isWrapperFor(Class&lt;?&gt; cl) throws SQLException {<a name="line.96"></a>
<FONT color="green">097</FONT>            return cl.isInstance(getUpdatedDataSource());<a name="line.97"></a>
<FONT color="green">098</FONT>        }<a name="line.98"></a>
<FONT color="green">099</FONT>    <a name="line.99"></a>
<FONT color="green">100</FONT>        // Internal methods<a name="line.100"></a>
<FONT color="green">101</FONT>    <a name="line.101"></a>
<FONT color="green">102</FONT>        private synchronized DataSource getUpdatedDataSource() throws SQLException {<a name="line.102"></a>
<FONT color="green">103</FONT>            if (!this.updated) {<a name="line.103"></a>
<FONT color="green">104</FONT>                if (this.dataSource == null)<a name="line.104"></a>
<FONT color="green">105</FONT>                    throw new IllegalArgumentException("no DataSource configured");<a name="line.105"></a>
<FONT color="green">106</FONT>                this.updateDataSource(this.dataSource);<a name="line.106"></a>
<FONT color="green">107</FONT>                this.updated = true;<a name="line.107"></a>
<FONT color="green">108</FONT>            }<a name="line.108"></a>
<FONT color="green">109</FONT>            return this.dataSource;<a name="line.109"></a>
<FONT color="green">110</FONT>        }<a name="line.110"></a>
<FONT color="green">111</FONT>    }<a name="line.111"></a>
<FONT color="green">112</FONT>    <a name="line.112"></a>




























































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